One problem that exists with cordless DC battery powered tools is the limited amount of charge that is able to be maintained and stored by its battery cartridge before it must be recharged. The confined amount of charge limits the amount of time that the power tool may perform until the cartridge needs to be recharged or replaced. Cordless power tools are often used in situations where an external alternating current (AC) power source is not immediately available for conventional AC power tools to be used. Many "on the job"or remote sites lack electrical service completely, thus making it impossible to use conventional AC power tools or to recharge the battery cartridges of cordless DC power tools
Devices that allow cordless DC power tools to be operated from an external DC power source (i.e. other than its own conventional DC power source/battery cartridge) have been developed. See, e.g., U.S. Pat. Nos. 5,076,805; 4,835,410; and 5,715,156. These devices generally comprise an adapter or insert with contacts that generally insert into the area where the battery cartridge would normally be inserted. The contacts of the adapter or insert are coupled to the power contacts of the power tool. External power source couplers are provided for coupling the power tool to an external DC power source, and a cord of fixed length coupled between the adapter or insert and the external power source coupler provides user length or distance between the power tool and the external power source. However, a major problem with the provided cord is that it is fixed in length and cannot or is not able to be readily adjusted or varied to a generally desired or convenient length.
Therefore, the need exists for devices and methods that allow cordless DC power tools to be operated from an external DC power source (i.e. other than its own conventional DC power source/battery cartridge) wherein the devices and methods allows coupling of the DC power tool to an external DC power source and allows the cord or cords between the adapter or insert and external power source coupler to be more easily or conveniently adjusted or varied to a generally desired or preferred length for the user.